Improvement in lifting-jacks



LORENZO D. WARREN, OF HAVANA, ILLINOIS.

Letters Patent No. 108,414, dated October 18, 1870,

lMPRGVEMENT lN LlFTlNG-JACKS.

The Schedule referred to in these Letters Patent and making part of the came.

To all whom it may conce/.

Be it known that I, Lon'nzvzo D. Wannes', of Havana, in the county of Mason and State of .lllinois, have invented a new and improved Lifting- Jaek; and I do hereby declare that the following is a full, clear, and ex-aet description thereof, which will enable others skilled in the arb to make and use the same, reference being had to the accompanying drawing,r forming part ot' this specification.

Figures l and 2 represent sideviews of' my iinpioved lil'tingjjack, showing it in different positions.

Similar letters oi' reference indicate corresponding parts. l

This invention relates to a new lifting-jack, which is of extremely simple construction, and on which no pawls, clamps, onserews are required.

rlhe invention consists in the combination cfa, lifting-lcver with a pivoted post and slidingarm, all parts being so arranged that they will operate without additional apparatus. "Ille simplestaml most practical device of the kind is thereby produced.

A in the drawing represents the supportingbed or platform of my improved lifting-jack.

From itprojects an ear, a, to which, by means of a pin, b, one arm, c, of :i T-shaped level', E, is pivoted.

,lo the other arm, d, ofthe lever B is pivoted, by a pnc, the lower end of a port, O.'

1) is the supporting or lifting arm of the jack.

It has at one end :in eye, f, which embraces the post U.

y means of' this eye the arm can be readily adjusted upor down on the post. Vhen, however, a weight rests upon the arm D, the same will be 'so inclined as to bend with two diagonally-opposlte corners against; the edges ofthe post. Thereby the arm is locked to the post. p

As long as the lever B is swung up so that its arms c fl will be nearly in a horizontal position, asin lie. l, the device will be in position to receive a weight. By then swinging the lever down, to bring the arms c d into'a nearlyr vertical position, as in iig. 2, the weight; on the arm D will be raised.

I am aware that a T-shaped lever and lifting-rod or bar have been combined hei'ore with lifting devices, but

What l claim as my invention, and desire to protect by Letters Patent, isW

The combination, with a' T-shaped vibrating lever, B, and lifting-bar C, of a xed l'ulc1um, resting on the bed A al, and the adjustable hook-arm D,all constructed and relatively arranged as and for the purpose speciiied.

LORENZO D. WARRE.L Witnesses:

JACOB WHEELER, W. J. ODLE. 

